Fantastic plastic

Charlotte Williams is a reader in Catalysis and Polymer Chemistry in the Department of Chemistry. She talks to Reporter about making sustainable polymers.

What have you discovered?

A group of catalysts that enable a process, which uses carbon dioxide as a raw material to make polymers or plastic materials.

How is your discovery unique?

The reaction was first discovered in Japan in 1969. However, at that time, the catalysts that the scientists were concentrating on, required high pressures of CO2 to work and actually emitted more CO2 than they consumed, making it unsustainable. The catalyst which we are using is quite different. Up until now, most of the research in this area focused on catalysts with a single metal centre, but we decided to target binuclear catalysts, in other words, those that have two metals in very close proximity to one another.

How did you discover this catalyst?

It was a quite deliberate project. Research papers have, for some time, indicated that binuclear catalysts are key to making the process more sustainable, so we decided to test several metals. We screened many and it took three years to find this successful group of catalysts.

How is the process you have discovered more sustainable?

The catalyst we use enables the process of making polymers to occur at one atmosphere pressure of CO2. This is significant because it’s the kind of pressure of CO2 that you might find produced in industrial processes like power generation, cement manufacture, or fermentation.

How will your discovery benefit society?

There is an increasing consumer demand for sustainable polymers. The catalysts we have discovered are very stable and tolerant of water, and can be handled without special operating procedures in the air and in the laboratory. This makes the process of producing polymers from CO2 much more feasible.